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To round a number means to create an approximate value. If you’re measuring the distance from one side of the street to the other and have a measurement of 37 feet, inches, you probably don’t need a number that precise. Depending on what you’re doing, you may be fine with 37 feet — which is the number rounded to the nearest foot. Or 37 feet 3 inches may do it for you. It just depends on the circumstances.

To round decimal numbers:

1 Determine the number of places you want and look one further to the right.

2 Increase the last place you want by one number if the one further is 5 or bigger.

3 Leave the last place you want as it is, if the one further is less than 5.

The symbol ≈ means approximately equal or about equal. This symbol is useful when you’re rounding a number.

Here are some examples of rounding each decimal to the nearer thousandth (three decimal places):

Q. Round 0.363636 to the nearest thousandth.

A. 0.364. When rounded to three decimal places, you look at the fourth digit (one further). The fourth digit is 6, which is greater than 5, so you increase the third digit by 1, making the 3 a 4.

Q. Round 0.03125 to the nearest thousandth.

A. 0.031. When rounded to three decimal places, you look at the fourth digit. The fourth digit is 2, which is smaller than 5, so you leave the third digit as it is.